This application claims priority to and the benefit of the filing date of German Application No. 199 47 329.3-27, filed Oct. 1, 1999, hereby expressly incorporated by reference.
The invention relates to a device, by which printed products conveyed on a conveying belt, in particular in scale-shaped configuration, are vertically stacked and dispensed in partial stacks of a desired number.
Printed products are conventionally compiled and packaged in stacks for transport. This requires partial stacks to be formed, each comprising a certain number of printed products. Conventionally, the printed products conveyed, e.g. in a scale-shaped or overlapping configuration, on a belt conveyor are dropped into a vertical collecting shaft. An openable stacking support, on which the stacks are formed, is disposed within said collecting shaft.
In order for such a stacking device to be used in diverse ways and thus to pay off quickly, it is desirable to use a collecting shaft which is adjustable in format.
Once the desired number of printed products for one partial stack has been achieved, the stacking support is opened, and the partial stack thus formed is ejected in downwards. The operation of opening the stacking support, ejecting the partial stack and closing the stacking support again requires a certain time. In order to prevent subsequent printed products from being included in the ejected partial stack or from being stuck in the closing stacking support, the stream of printed products has to be briefly delayed.
DE-U 1-93 17 919 suggests to provide several horizontally displaceable and thus openable and closeable stacking supports shaped like rakes below one another within said collecting shaft. A stack is then formed on a lower stacking support. By closing an upper stacking support, the formation of the stack is concluded. The completed stack is transferred by opening a lower stacking support. Upon closing of the lower stacking support, a new stack may be formed on the lower stacking support by opening the upper stacking support and dropping the printed products meanwhile compiled thereon. This cycle may be further perfected by providing three stacking supports disposed below one another.
That embodiment has the disadvantage that the throughput of printed products thus achieved is limited, to ensure that printed products dropping into said collecting shaft after one another have a certain distance between them, and so that, upon closure of the upper stacking support, the rake may be passed, without any problem, between two printed products consecutively dropping into said collecting shaft.
Although it is contemplated in that embodiment to provide a collecting shaft which is adjustable in format, larger formats increase the risk of the rake not being passed properly between two consecutive printed products. Products of a large format tend to drop into the collecting shaft in a slanted or bulged position. Therefore, even larger gaps must be observed between consecutive printed products in order to exclude malfunctions. The achievable throughput is thus further reduced.
JP-A 2-3-288764 discloses that disruptions may be achieved in a stream of printed products conveyed in scale-like configuration by passing a separating plate, which initially extends into the collecting shaft above the scale stream on the side of the collecting shaft facing away from the belt conveyor, down into the scale-like stream. Those printed products which have already been conveyed completely into the collecting shaft, are pushed down by the separating plate. Subsequent printed products will slide over the separating plate and form a stack thereon. During this movement, the separating occupies the major portion of the cross-section of the collecting shaft. The separating plate is then guided downwards, withdrawn from the collecting shaft in a horizontal direction, while unloading the printed products collected thereon, and then moved back into the starting position.
That embodiment has the disadvantage that it requires a very complicated set-up of equipment. The separating plate has to be guided back to the top on the outside of the collecting shaft over a considerable distance, thus requiring a considerable amount of space. In addition, the movement of the separating plate requires a certain amount of time due to its considerable mass. Thus, a high throughput can be ensured only by providing several separating plates. For a collecting shaft being adjustable in format, the apparatus would be even larger and more complicated.
Accordingly, it is an object of the invention to provide a device for vertically stacking printed products, which is adjustable in format, allows a high throughput without being prone to malfunction, while not requiring a very complicated construction.
According to the present invention, this object is achieved by a device for vertically forming partial stacks of printed products, which comprises a belt conveyor for transporting printed products, in particular in at least partially overlapped or scale-formed configuration; a bulging device, by which the printed products conveyed on the belt conveyor may be provided with a convexity around an axis extending in the conveying direction of the belt conveyor, a vertically extending collecting shaft, adjustable in format and disposed at one end of the belt conveyor in the extension thereof such that printed products conveyed on said belt conveyor drop into said collecting shaft, which has an openable stacking support disposed therein, on which a stack of printed products may be received, and a first supporting finger, disposed on the side of the belt conveyor facing away from the collecting shaft and above the stacking support, said finger being displaceable by a displacing device from a starting position, in which it extends centrally into the collecting shaft above the stream of printed products, vertically downwards into said stream of conveyed printed products, such that subsequently conveyed printed products are placed on said first supporting finger, which is then horizontally displaceable out of the collecting shaft such that the printed products placed thereon drop into said collecting shaft, and said finger being displaceable back into its starting position.